I created a simple shortcode to wrap around the selected text with a box. It's working fine if I write the shortcode manually, which is
But, the problem is with the shortcode button on the Rich text editor. When I click the assigned shortcode button to a selection of text consisting 2 paragraphs or more (i.e. contains a linebreak/ ), suddenly it gives this code around the [do action="tbw"]. (I found out using inspect element tool on Google chrome)
<span style="overflow:hidden;line-height:0px" data-mce-type="bookmark" data-mce-style="overflow:hidden;line-height:0px">[do action="tbw"]</span>
This code is filtered out when switching to the HTML view or publishing the post. So it essentially delete the [do action="tbw"] part of the shortcode, leaving many meaningless [/do] at the end of the selected texts.
I'm still trying to find out what causes this, disabling all plugin & switching to default theme does not solve the problem.
Any clues on what that data-mce-style/data-mce-type code might be?